Multiple level lighting systems, such as three level lighting systems, are used in various lighting applications. For example, three level lighting systems are commonly used in overhead lighting. Such lighting systems allow for conserving energy, because they allow a portion of the lighting to be turned off when the full light level is not necessary.
A typical implementation of a three level lighting system includes three power switches and three ballasts, where each power switch controls only one of the ballasts. Turning on all three of the switches at the same time powers the three ballasts, thus producing full light output. Turning on only two of the switches applies power to only two of the ballasts, producing a reduced light level and a corresponding reduction in power consumed. Turning on only one of the switches applies power to only one of the ballasts, resulting in a further reduced light level and a corresponding reduction in power consumed.